Herbig Haro 111:
A Pulsed Astrophysical Jet
Jets or beams of gas are a common phenomena in astrophysics.  Astronomers see high speed jets being beamed out many environments including stars that are just forming as well as the heart of giant galaxies.  The  image you see here is of Herbig-Haro  111.  The young star  star which formed this jet is at the bottom of the picture surrounded a disk of gas.  The knots above the star form due to pulses in the jet beam.  For reasons astronomers still do not understand these jets seem to turn on and off periodically like a garden sprinkler. The size scale of the jet is about one thousandth  of a light-year. There are other examples of pulsed jets.  Some of the jets come from young stars and others come from regions around black holes! Click on the images below to see some more.